U.S. Pat. No. 3,468,894 discloses the 1-unsubstituted 3-methyl-2-(3- or 4-pyridyl)indoles as diuretic agent. 2-(2-Pyridyl)indole-3-(acetic, propionic) acids are reported, e.g., in Pharm. Bull. 4, 16 (1956) and Chemical Abstracts 64, 19540d (1966) respectively. Various optically substituted 2-(3-pyridyl)-indole-3-acetic acids are described as chemical intermediates in Bull. Soc. Chim. France 1966, 771-2 and Bull. Soc. Chim. France 1969, 4154-9. The preparation of 1-cyanoethyl-2-(2-pyridyl)-indole is reported in Pharmazie 23, (10), 557-60 (1968).
Reported as thromboxane synthetase inhibitors are, e.g., 3-(imidazol-1-yl-alkyl)indones of U.S. Pat. Nos. 4,217,357 and 4,273,782, and 1-substituted imidazoles, e.g., U.S. Pat. Nos. 4,226,878 and 4,256,757 and British Patent Application Nos. 2,016,452A and 2,038,821A.
The present invention is concerned with the 2-(pyridyl and imidazolyl)-indoles of formula I which are useful as surprisingly potent and highly specific thromboxane synthetase inhibitors.
The foregoing attributes render the 2-(heteroaryl)-indoles of this invention particularly useful when administered, alone or in combination, to mammals, e.g. for the treatment or prevention of diseases responsive to the inhibition of thromboxane synthetase, comprising cardiovascular disorders such as peripheral vascular diseases and Raynaud's syndrome, thrombosis, atherosclerosis, coronary spasm, arrhythmias, cerebral ischaemic attacks, migraine and other vascular headaches, myocardial infarction, angina pectoris, hypertension; respiratory disorders, such as asthma and apnea; and inflammatory disorders.